I. Field
The present invention relates generally to communication, and more specifically to techniques for switching reception between multimedia streams.
II. Background
A wireless communication system may simultaneously transmit multiple data streams for broadcast, multicast, and/or unicast services. A data stream is a stream of data that may be independently received by a wireless device. A broadcast transmission is sent to all wireless devices within a coverage area, a multicast transmission is sent to a group of wireless devices, and a unicast transmission is sent to a specific wireless device. For example, a base station may transmit a number of data streams for multimedia (e.g., television) programs via a terrestrial radio link for reception by wireless devices within the coverage area of the base station.
A wireless device may receive only one of the multimedia programs transmitted by the base station at any given moment. To receive this program, the wireless device identifies all data streams transmitted by the base station for the program, determines pertinent parameters for each data stream of interest (e.g., how and where each data stream is transmitted), decodes each data stream in accordance with these parameters, and further processes each decoded data stream to generate an output suitable for presentation to a user. The wireless device continuously decodes the data streams for the selected program and provides decoded data in a streaming manner as long as the program is selected for reception.
If the user selects another multimedia program for reception, then the wireless device typically needs to perform a set of tasks in order to acquire, decode, and display the new program. These tasks may include terminating the decoding and processing of the current program, identifying all data streams transmitted by the base station for the new program, determining pertinent parameters for each data stream for the new program, and decoding each new data stream in accordance with its parameters. The wireless device may “freeze” the display with the last decoded frame for the old program or “blank” the display with a blue or black background during the time that the device is performing the tasks for the new program. The amount of time needed to acquire and decode the new program may be relatively long (e.g., over 1 second) for some wireless systems. In this case, freezing or blanking the display for the entire time duration may prove “annoying” to the user.
There is therefore a need in the art for better techniques to switch reception between multimedia programs.